Comparison of geogrid and geotextile reinforced earth slabs

Abstract

Presented herein is a comparison of the results of laboratory model tests used to study the bearing capacity of geogrid and geotextile reinforced earth slabs. The parameters studied were the coefficient of friction between the geotextile and the soil, pull-out resistance between the geogrid and the soil, depth below the footing of the first layer of reinforcement, vertical spacing of the layers, number of layers, width size of a square sheet of reinforcement, and tensile strength of the reinforcement. For both geogrids and geotextiles, after an optimum number of layers or width of reinforcement, the bearing capacity did not increase. In addition, the bearing capacity was largest for those geogrid and geotextile reinforced earth slabs where the first layer was closest to the footing and the spacing between the layers was the smallest. Bearing capacity increased directly with increasing reinforcement tensile strength for the geotextile; however, for the geogrid, aperture size and reinforcement tensile strength must be looked at simultaneously. Key words: reinforced earth slab, geogrid, geotextile, bearing capacity, pull-out, friction.

Numerical Investigation Into the Behavior of Circular Pad Shallow Foundations Supported by Geogrid Reinforced Sand

“…These results confirm the findings by Sing [11] , which were based on the study of square footings on sand reinforced with mild steel grids (optimum depth ratio was about 0.25). However, the results are in contrast with reports of other researches [7,12,13] , which, most likely is due to difference in material properties and the geometric dimensions of the foundation and reinforcement. Hence, it may be concluded that; reporting a single value of u/B for optimum bearing capacity of geogrid reinforced soil is flawed as reported by other researchers such as; Adams and Colin [2] , Yetimuglu et al [4] , and Guido et al [8] .…”

“…This value is slightly higher than 0.15-0.25 suggested by others [4,11] . Furthermore, Guido et al [7] , and Akinmusuru and Akinbolade [12] reported that, as the vertical spacing increases, the BCR value decreases accordingly. Guido et al [13] , indicated that, although the BCR value decreased with increasing vertical spacing, the trend of BCR variation with vertical spacing was different for different geogrids.…”

“…Detailed investigations have been performed using small scale laboratory test models and a (limited) number of in-situ tests [1,2,3,4,5,6,7,8 ] These studies (among others) have demonstrated that; a geosynthetic reinforcement placed below a foundation can increase both, the ultimate bearing capacity, and allowable bearing stress at a given settlement. However, due to the numerous parameters effecting the bearing capacity of shallow foundations and, limited literary records that predict the global effects of the physical and strength specifications of reinforced sand embankments, strength parameters of geogrid reinforcement, consider found action conditions and lack of research into geogrid reinforced circular foundations, more research is required to understand this emerging technology.…”

Effects of the first reinforcement depth for different types of geosynthetics

“…There is only limited information in the literature about the effect of different reinforcement types. Guido et al [22] and Chen [23] have investigated the reinforcement types and the general outcome was that geogrids show superior performance compared to geotextiles. Mandal and Manjunath [24] investigated the bearing capacity behavior of Geogrid and bamboo stick reinforcements for strip plates on dense sand.…”

Numerical analysis of shallow foundations on geogrid reinforced soil

“…Since the original work by Binquet and Lee, several laboratory model test studies have been published relating to the improvement of the load-bearing capacity of shallow foundations supported by sand reinforced with various materials such as geogrids [3,4], geotextiles [5], rope fibers [6], metal strips and metal bars [7][8][9][10][11][12].…”